57
THE INTEGRATED WORKFLOW AND SOFTWARE SYSTEM FOR GIS
DATABASE UPDATE BASED ON GEOSPATIAL IMAGIES
Wang Mi a , Hu Fen a , Liao Anping b , Lu weihua\ Zhang Liyong 3
“State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing (LIESMARS)Wuhan
University 430079, China
b National Geomatics Centre of China, No 1 Baishengcun Zizhuyuan, Beijing 100044
KEY WORDS: GIS Database Update, Geospatial Images, Integration, Multi-Source Information Conformity, Scheme
Configuration
ABSTRACT:
Although the image-based update strategy is becoming one of the most desirable choices in keeping the up-to-date state of GIS
database, now in China, the traditionally adopted workflow and arts for update are still scarcely affected by the current advanced
technologies and methods, which is quite inharmonious with the high demand for fast data update. Considering the current technical
and financial feasibilities in practical applications, this paper studies on the design aspect of the efficient software system for GIS
database update based on geospatial images, in which the operation mode of integration is emphasized; next, a brief discussion of the
system function architecture also is included; finally, the integrated software system Geomapupdate for national 1:50000 GIS
database update based on geospatial images is introduced, as a typical case study. It is a platform exclusively servicing the current
GIS database update businesses of our country and supported by National Geomatics Center of China (NGCC) and designed by the
research group of State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing (LIESMARS)
Wuhan University. Practices manifest that Geomapupdate is a successful case study attempting to realize the highlighted integration
concept for GIS database update; and it is able to improve the traditional update efficiency by more than 20%, which has been
witnessed in the 1:50000 GIS database update business of China recently and laid a base to achieve rapid updating GIS data.
1. INTRODUCTION
The up-to-date state is the key factor that evaluates the
utilization value of GIS databases, which becomes the focus in
the application field of GIS at both home and abroad nowadays
(Speren 1996; Dowman 1998; Fritsch 1999; Jiang and Chen
2000; Chen et al., 2004; Dekker 2004; Bouziani et al., 2007).
In china, construction of the national fundamental geospatial
database has been completed in the past “tenth five-year plan”,
and the primary task has turned to the geographic database
updating aspect in the new “eleventh five-year plan”, during
which State Bureau of Surveying and Mapping enlarges the
capital, material and labour input, planning to organize the
domestic surveying and mapping departments to jointly
complete the updating mission of the national 1:50000 GIS
database, mainly through the approaches of image-based
integrated interpretation and surveying or map generalization.
Under the new circumstance, many spatial data producing
departments gradually transfer the traditional collecting-
oriented data producing mode into the updating-oriented data
refinement mode, during which continuous explorations and
achievement are made to the advanced methodologies for
spatial data update. The quick and sustainable GIS database
update is closely linked with the continuing up-to-date data
sources and efficient mechanisms for update. With the rapid
development of airborne and spacebome sensor technologies,
now it is easy to acquire the real-time or near real-time high-
resolution images of land covers; meanwhile, the intelligent
combination of imaging sensors with various additional sensors
also contributes to the gradually automated and intelligent data
processing technology. All of these developments indicate that
the image-based updating strategy is a most desirable choice for
GIS database update, due to the abundant up-to-date
information it provides (Gunst and Hartog 1994; Knudsen and
Olsen 2003; Holland et al., 2006).
However, in China, the update workflow in traditional
operation mode is fixedly followed by three main steps: image
interpretation indoors, field validation and supplement, data
revision indoors. Such a serial workflow is unsuitable for the
fast GIS database update command due to the long updating
cycle induced by the disjointed indoor and field working mode.
The current field validation and supplement mode is scarcely
renovated by the contemporary electronic technology and
almost continues to adopt the traditional analogized photo or
printed map based surveying and revision pattern, incurring
disharmony and inconvenience in operation consistency and
information sharing between the work indoors and in field.
Besides, there is a vacancy in the integrated software system
exclusively provided for the current image-based data updating
business, so much so that the accomplishment of workflow has
to rely on combined operations on software from different
specialized fields, e.g. Arclnfo, Maplnfo, Photoshop etc.,
without a uniform criterion for professional operators to comply
with, which to great extent increases the operation complexity
and discontinuity. All of these limitations have been exposed
during carrying out the traditional GIS database update business
based on geospatial images. Considering the problems from
both efficiency and quality aspects, reformation of the
traditional image-based update methodology relies on the full
realization of the integrated workflow and software system
based on which the update process is carried out.
Regarding the technical and financial feasibility in practice, the
second chapter of this paper explores on the design aspect of the
efficient image-based software system for GIS database update,
in which the operation mode of integration is discussed in detail;